exposure time
what are the values of the exposure time in millisecond. i know that the values are from -1 to -12
View Articleopencv_traincascade: obtaining number of features per stage
I'm using opencv_traincascade: How can I check how many features are being learned at each stage of the training cascade?
View Articleopencv_traincascade detection phase: obtain confidence of each detection window
Has anyone created a recall precision curve for traincascade? I am thinking of doing this at the detection stage: Looking at the...
View ArticleHow to know if device is compatible with OpenCV using OpenCL
In this [post](http://answers.opencv.org/question/66419/minmaxloc-crashed-using-opencl-when-location-is-needed/) I think I have found a bug in opencl using opencv for graphics card GeForce GTX 970. Is...
View Article3D rotation matrix between 2 axis
I have 2 known 3d points which are the origin of 2 axis plot in the space and I need to compute the 3D rotation matrix between them. I didn't really get what the difference Euler angles and the other...
View Articleopencv_traincascade preprocessing
I have seen folks use equalizeHist as follows: gray = cv2.equalizeHist(gray) detections = cascade.detectMultiScale(gray) where gray is the image being tested during the detection phase of ViolaJones....
View ArticleHow to read a Matrix from a child node with FileStorage API
Hello guys, I am having a little issue here. I saved a couple of mat as child nodes in xml using the Filestorage API in opencv. However when i try to read them back the filestorage API reads the same...
View ArticleStereoRectify with a single moving camera
Hello, I am looking to make use of the stereoRectify function, but am unsure how I should calculate the rotation matrix R and translation vector T. I know typically these come out in the wash if you...
View ArticleIs there a python API equivalent of cvGetWindowHandle()?
Hi everyone, I've been searching for a solution to this common problem that myself and others seem to have when closing a window from a feed by clicking one the window's "X" button instead of pressing...
View ArticleSimulate long exposure from video frames OpenCV
I am trying to simulate a long exposure photo by combining images(frames) into one image and by performing operations based on a preset alpha. I am doing this on an iPhone, and I currently have the...
View ArticleAndroid eyes detection
Hello guys, Im REALLY new with OpenCV and Im trying to learn how to use it. I'm doing a little project to my college and I need to use OpenCV to detect both eyes (open) from people, the return need to...
View Articleimage segmentation
I wonder if there are algorithms used to segment images efficiently. The ones I tested by now can not segment hair correctly as on this image: ![enter image description here][1] I just want to know if...
View Articlereplacement for Watershed ?
Which algorithms similar to Watershed are efficient for region based segmentation. For my application watershed didn't detect the regions correctly. i created the markers using morphological operations.
View Article3.0 Core_PCA.accuracy test failed
Hi, Just install opencv 3.0 in my Ubuntu 14 box. Run the opencv_test_core and it failed one test Core_PCA.accuracy. What could possibly cause this issue? Thanks, Thomas
View ArticleException deep inside OpenCV code
I am writing code to perform background subtraction. The relevant part of the code is: cv::Mat fg_mask; // Foreground mask generated by MOG2 method cv::Ptr mog2; // MOG2 background subtractor mog2 =...
View ArticleCan OpenCV do these processing?
I am working on an OCR project. I need to do some pre-processing similar to the link below: http://cn.mathworks.com/help/vision/examples/automatically-detect-and-recognize-text-in-natural-images.html...
View Articlebug in ocl_bilateralFilter_8u
Hi, The bilateralFilter is used in the video image processing, and after about one hour or more, a dump happens. That's memory Free or allocator breakpoint. The call stack reports the location is in...
View Article3d calibration
Hi ! I'm using the sample project for the 3d calibration, my question is about the input file the XML file. I don'T understand what I should but square size , is it the size in millimeter ? and what do...
View ArticleIs there any reason not to use UMat?
I'm currently writing a piece of software that uses various different modules of OpenCV (some examples are edge detection via Canny, filtering operators, optical flow and I have some own algorithms...
View ArticleEstimate occluded marker's position based on its last known position and the...
Hi everyone, I'm currently developing a marker based pose estimation application that calculates the pose of a flying kite based on a camera facing down along its rope. I'm using the Good features to...
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